1. Field of the Invention
The present invention relates to a liquid crystal display having a structure in which a lamp cover and a mold frame are fixed each other and to a method for manufacturing the liquid crystal display comprising a step of fixing the lamp cover with the mold frame.
2. Related Art Statement
FIG. 12 shows one example of the internal structure of a prior art liquid crystal display which mainly comprises a liquid crystal panel 101 provided with a printed circuit board for driving the liquid crystal, a lamp unit 102, a lamp reflector 103, a lamp cover 104, a light guide plate unit 105, a mold frame 106 for supporting and fixing the liquid crystal panel 101 and the light guide plate unit 105, a screw 114 for fixing the lamp cover 104 and the mold frame 106 and a front frame 107 fixed on the upper face of the liquid crystal panel 101. In the liquid crystal display constructed as described above, the lamp cover 104 and the mold frame 106 are fixed from each other by using the screw 114.
FIG. 13 is an enlarged perspective view showing part where the lamp cover 104 is fixed with the mold frame 106. As shown in FIG. 13, when the lamp cover 104 is fixed with the mold frame 106 by using the screw 114, the thickness of the liquid crystal display has been thickened by the thickness of the screw, i.e., by the thickness of the lamp cover 104 and the screw 114 projecting out of the surface of the mold frame 106.
Japanese Patent Laid-Open No. Hei. 9-81050 has disclosed a method for fixing a light guide plate with a circuit board which are components of a liquid crystal display as another prior art. Although it has disclosed the structure for mounting the light guide plate by fixing it with the circuit board by thermal caulking or a fixing claw, it has disclosed no means for fixing the lamp cover with the mold frame.
In view of the problem described above, the present invention proposes a novel liquid crystal display which may be thinned by improving means for fixing the lamp cover with the mold frame.
The invention also proposes a method for manufacturing a novel liquid crystal display by improving the process for fixing the lamp cover with the mold frame.
An inventive liquid crystal display comprises a liquid crystal panel; a light guide plate unit for spreading light emitted from a lamp unit to the back of the liquid crystal panel; a lamp cover surrounding the lamp unit; and a mold frame supporting the liquid crystal panel and the light guide plate unit. In the liquid crystal display, the lamp cover is fixed to the mold frame by caulking projections provided so as to project from the lamp cover to the mold frame to receiving holes provided through the mold frame in areas where the lamp cover overlaps with the mold frame.
In the inventive liquid crystal display constructed as described above, the projection is provided with a plurality of projecting pieces and the lamp cover is fixed to the mold frame by bending and caulking the edge of the projecting pieces at least into two different directions, respectively.
In the inventive liquid crystal display constructed as described above, the projection is a projecting piece which extends in one direction along the surface of the lamp cover and the receiving hole is opened in slit along the direction in which the projecting piece extends.
In the inventive liquid crystal display constructed as described above, the projection is a projecting piece which is formed by bending up a notch provided at the edge of the lamp cover and the receiving hole is formed by a cutaway section provided at the edge of the mold frame overlapping with the area where the projecting piece is formed.
In the inventive liquid crystal display constructed as described above, the section of the receiving hole of the mold frame where the edge of the projection contacts is cut aslant, is provided with a step or is rounded.
In the inventive liquid crystal display constructed as described above, the edge of the projection caulked to the receiving hole stays within the receiving hole and does not project out of the surface of the mold frame.
In the inventive liquid crystal display constructed as described above, the projection is cylindrical and is caulked to the mold frame by its peripheral edge portion.
An inventive manufacturing method of a liquid crystal display comprises steps of forming projections which project out of the surface of a lamp cover at part of the lamp cover surrounding a lamp unit for illuminating light to a liquid crystal panel; opening receiving holes which penetrate through the mold frame at areas of the mold frame for supporting the liquid crystal panel and a light guide plate unit which spreads light to the back of the liquid crystal panel; and fixing the lamp cover to the mold frame by inserting the projection through the receiving hole and by bending and caulking the edge of the projection.
In the inventive manufacturing method of the liquid crystal display composed of the steps described above, the projection is provided with a plurality of projecting pieces and the edge of the projecting piece is bent at least into two different directions, respectively, in caulking the projecting piece to the receiving hole.
In the inventive manufacturing method of the liquid crystal display composed of the steps described above, a working jig having a working plane for forming the edge of the projection along the shape of the section of the receiving hole is used to bend and caulk the edge of the projection by pressing it to the edge of the projection.
The specific nature of the invention, as well as other objects, uses and advantages thereof, will clearly appear from the following description and from the accompanying drawings in which like numerals refer to like parts.